Boiler



(No Model.) 2 sheets-sheen 2.

T. L. sa T. J. STURTBVANT.

' BOILBR.

110.422,995. Patented Mam.. 11,1890.

N4 PEYERS Pnnwuxhognphen wnshingwr D, C.

UNITED STATES PATENT OFFICE.

THOMAS L. STURTEVANT AND THOMAS J. STURTEVANT, FRAMINGHAM,MASSACHUSETTS.

BOILER.

SPECIFICATION forming part of Letters Patent No. 422,995, dated Marchl1, 1890,

Application filed November 9, 1889. Serial No. 329,829. (No model.)

To all whom it may concern:

Be it known that we, THOMAS L. STURTE- VANT and THOMAS J. STUETEVANT,citizens of the United States, residing at Framingham,

in the county of Middlesex and State of Massachusetts, have inventedcertain new and useful Improvements in Boilers; and we do hereby declarethe following to be a full, clear, and exact description of theinvention, such ro as will enable others skilled in the art to which itappertains to make and use the same, reference being` had to theaccompanying drawings, and to figures of reference marked thereon, whichform a part of this specification.

This invention relates to boilers, particularly that class provided withhollow tubes y closed at one end and connected with the boiler-shellexteriorly of the latter, such tubes 2o being generally termedwater-legs.

` The essential feature of ourinvention is in connection with a seriesof erect or rising water-legs, as likewise a series of pendentWater-legs.

In the upright series our invention pro- Vides for a free escape ot'steam at the closed ends of said tubes, and thus facilitates thecirculation, while in the pendent water-legs a similar arrangementpermits the closed end 3o of said water-legs to be freed from sedimentor other deposits which tend to collect at such points.

Our invention further consists in the general arrangement of parts, thenovel and advantageous features of which will be more fully hereinafterexplained.

The drawings represent in Figure l a longitudinal vertical sectionalelevation. Fig. 2 is a vertical cross-section. Fig. 3 is a verticalcross-section showing omission of waterlegs at a point directly over thegratefbars.

The object of our present invention is to produce a boiler of that classas above premised, in which a constant water-level is to be maintained,one which consequently has a free circulation. This boiler also is oneof large steam-generating surface. To this end we have formed a boileror water-reservoir proper 2, of any desired shape, preferably as- 5oshown, or rectangular in cross-section, with convex or rounded sides andsuitably stayed or bolted. This water-reservoir may be a cylinder orconsist of one or more tubes arranged in series. Said boiler,preferably, is not set horizontally, but inclines upwardly toward thegrate-bars. Such deviation from the horizontal is to enable the seriesof wateriegs with which it is to be furnished tobe set at right anglesin the boiler-shell and at the same time have them present the bestpossi- 6o ble surface for heating, as likewise the best position foractive circulation. These waterlegs consist in the present instance oftwo series of tubes-an upright set 3 and a pendent set ete-all connectedwith the boiler-shell and communicating therewith, but closed at theouter ends. Furthermore, said tubes are arranged in rows transversely ofthe boiler its entire length.

Heretofore an upright closed water-leg 7o could not be employed, for thereason that there was no escape for the conned air and steam. Toovercome such objections, we have disposed longitudinally within eachwater-leg of the upright series 3 a small pipe 5. The 75 latter are openat their upper ends and are united with a steam-conveying pipe 6, closedat the rear end. 'Said pipe extends nearly the entire length of theboiler-shell therewithin, and connects with a h'ollow casting 7, 80"

from which the steam-pipe 23 leads. Thus the longitudinal rows ofwater-legs interconnect with a common steam-discharge by the series ofconveying-pipes 6. Consequently, as the water in the boiler is heatedand steam is generated therein, as likewise in the waterlegs, said steamis free to rise and escape at once by way of the individual outlet-pipes5 and series of pipes 6; hence it is evident that the circulation can berapid, since no 9o steam exists to retard it. Moreover, since thesteam-conveying pipes 6 are interiorly of the boiler, the pressure isbalanced and very thin light tubing can be used. Similarly, but for adifferent purpose, the pendent water-legs 4 are fitted with tubes openat both ends, termed Field tubes, each of the latter being provided withpipes 8 interiorly and open at their lower ends. Said pipes eX- tendupwardly and join a series of pipes 9. roo These pipes are the same innumber as the water-legs, taking the transverse rows, and

escape, sticking up and carrying oit all sedi-y ment which may havecollected at the closed ends of said tubes. f

By employing a small pipe 8 in lieu of the Field tube as a blowoft,which idea has been shown in a previous application now on file inthePatent Office, we obtain the same resuit-cleansing of the tubes-butwith a very much less loss in steam and water than if the Field tubeswere used for such purpose. The small blow-off pipes 8 are shown withinthe Field tubes; but we do not desire to be limited to this exactconstruction, since in many instances they can be located in the spacebetween the pendent leg and thel Field tube, and work nearly as well.

The steam-discharge pipe is shown at 23, and, as before stated, leadsfrom a hollow casting 7, in which all the steam-conducting pipes (i fromthe water-legs 3 terminate. Said pipe 23 extends above the uprightwater-legs within the boiler-casing l2. A separator 13, wherein thesteam is freed from any moisture which it may contain, may be situatedat the rear of the boiler. The upper part of such separator is connectedby the main supply 14 to the engine or other source to be provided withsteam, while the lower end is united by a pipe with the boiler proper, acheck-valve l5, being located within this pipe to prevent steam frompassing into the separator, which might occur in some cases.

A small portion of the upper end of the upright tubes, since awater-level is to be maintained, will be necessarily free from water. Toprevent such tubes from being highly heated and thus burning out, wehave arranged above the Water-reservoir of the boiler proper lalongitudinal diaphragm or partition 16, through which the uprightwater-legs extend, forming two iiues, direct and return, respectively 1920. Thus. the hot gases from the tire are obliged to pass first belowthe boiler proper, thence they return above the latter, but beneath thepartition'lG, coursing about the upright tubes by Way of the iiue 19;but only over such portions of these tubes as al ways contain water. Thegases, when they reach the front of the boiler, are now permitted toreturn above the partition through the tiue 20, passing about the upperextremities of the waterlegs; but since the heat is here very muchdiminished no harm occurs to the said water-legs.

By reference to Fig. 3 it will be seen that to permit the fire to bebrought within a suitable distance of the boiler proper we have omittedthe pendent water-legs for a space equal to the grate-surface, leaving,however, two rows, one on either side of the tire. By such arrangementof the upright tubes and by maintaining a water-level thereinwaterswashing within the boiler is prevented amuch-desired result inmarine boilers.

What we desire to claim is- 1. The improvements in steam-boilers,consisting, in combination with a water-reservoir, of a series ofupright water-tubes in which a waterlevel is to be maintained, saidtubes being closed at their upper ends and provided with steam-outlets,a pipe running the length of the water-receiver and connected to saidoutlets, and a hollow casting at the end of said Water-receiver intowhich` said pipe discharges, substantially as stated.A

2. The combination, with a central reservoir and a series of rising andpendent tubes closed at their outer ends, of a series of pipes, onewithin each closed tube, those within the upright tubes serving assteam-outlets, those within the pendent tubes as blow-ott pipes,substantially as herein specified. 3. In steam-generating apparatus, acentral water-reservoir,a series of pendent eXterior tubes closed at oneend and provided with tubes, combined with a pipe interiorly of thewater-reservoir, and a series of blowoft pipes to the main discharge otthe boiler, substantially as described.

4L. A steam and water reservoir, a series of pendent tubes 4, closed atone end, a series of tubes open at both ends, one within each closedtube, combined with pipes S, open at their outer ends, and a series ofblow-ott pipes 9, in which the individual pipes 8 terminate,substantially as herein specified and set forth.

5. In combination with a steam and water reservoir 2, the series ofupright and pendent tubes, as described, the partition 16, through whichthe upright tubes extend, a steam-discharge 23, the separator 13, theVpipes 5, 6, S, and 9, and the inclosingfcasing 12, as specified.

In testimony whereof we affix our signatures in presence ot" twowitnesses.

THOS. L. STURTEVANT. THOMAS J. STURTEVANT. Vitnesses:

H. E. LODGE, FRANCIS C. SrANwooD.

IIO

